@misc{indiciae47f52065ca8a,
  title = {Results of spirit leveling in Virginia, 1900 to 1913, inclusive},
  author = {Robert Bradford Marshall},
  year = {1914},
  doi = {10.3133/b562},
  url = {https://pubs.usgs.gov/publication/b562},
  note = {Source identifier: b562}
}